Mark,
September/October is good for Siem Reap - hot but not oppressive, and green.
That's really useful information. A combination of humidity and high temperature can be devastatingly oppressive. My 5D is not sealed. I'd hate to think that a profusion of sweat dripping from my face might seep into the controls. (Only kidding ).
If you hire a photo-savvy tour guide (with driver), they know the best times of the day for each structure, because they have guided previous rounds of photographers and know what photographers want.
I'm a bit ambivalent about that idea, but I had the experience. I was visiting a temple for the second time because on the occasion of the first time the place was swamped with tourists, each and every one insisting on having his/her photo taken in front of every tree root. I simply didn't have the time to hang around.
On the second visit, an unemployed guide saw me walking around a feature looking for an interesting angle. He jumped at the opportunity to make a dollar, approached me and said, 'Look! Just come over here. Stand here. See?'
The perspective was interesting, so thinking he was perhaps an expert photographer, I allowed him to show me around, realising of course I'd have to give him a tip. But most things are so inexpensive in Cambodia, I'd long since stopped haggling over trivial sums of money. (Not entirely, though ).
At every point, the guide said 'Stand here!' 'Come over here!'. Most of the perspectives were quite interesting. This was a great time saver. To find these perspectives I realised I'd be wandering around for a considerable time at each spot.
After an hour or so, as we'd completed the circuit, I said, 'So you're into photography?' ' No', he replied. 'I've just observed photographers taking photos at those spots'. My ego was deflated. My Gawd!, every Tom, Dick and Harry has got those shots, I thought.
Here's a couple of them . [attachment=156:attachment] [attachment=157:attachment]
By the way, I'm never quite sure what degree of sharpening is appropriate for small jpegs. The above images look a bit oversharpened to me. What do you think?
Bear in mind, these are not finished images. Conversion from RAW in ACR was completely automatic. I did a tweaking in levels, a slight bit of 'local contrast enhancement' and a couple of passes in Focus Magic. That's all.
Feed back would be appreciated.
ps. These images are not even cropped.